This invention relates generally to insulated refrigerator door panels, and more particularly to refrigerator doors having a dispensing mechanism such as ice and water dispensers mounted in the door for access from the exterior of the refrigerator without the need for opening the door itself.
Refrigerator doors are generally formed from an outer panel or shell formed from sheet metal which generally may be prepainted prior to forming. This shell is formed from a single piece of sheet metal such as steel to define a rectangular front face, with inturned edges that form the sides, top and bottom of the door panel. The sheet metal is further bent inwardly around all four sides to define a short lip extending parallel to but spaced from the front panel face. The door also includes a liner, preferably formed from plastic, shaped to provide shelves and other storage features on the inner face and this panel is attached to the inturned lips of the shell by fasteners which also serve to hold in place a magnetic rubber gasket that serves not only as a seal between the door and the rest of the cabinet but, as a result of magnetic attraction, holds the door in a closed position.
The space between the liner and the shell is generally filled with insulation, and while fiberglass has been used in the past, it has been found that superior results are obtained by using a rigid insulating polyurethane foam which generally forms a layer the thickness of the shell between the face and the inturned lips and such arrangement has been shown in the patent of David J. Donaghy, U.S. Pat. No. 4,955,675, granted Sept. 11, 1990 and assigned to the Assignee of the present invention. The use of such foamed in place polyurethane foam not only provides improved insulating values necessary for increased energy efficiency that is now required for appliances such as refrigerators, and also provides increased rigidity to the door by bonding to the liner so that the liner can use thinner metal without loss of strength.
The above described arrangement has worked quite satisfactorily with doors having a flat, uninterrupted face but heretofore has not been suitable in the case of refrigerator doors that have an ice and water dispensing unit mounted in one of the doors. These units are usually mounted in the freezer door on a side-by-side refrigerator but are also used on large top freezer refrigerators, in which case the dispenser is mounted on the lower or food compartment door.
In addition to problems of mounting the dispensing unit itself on the door, it is also necessary to provide a water tube and electrical connection to the rest of the refrigerator to supply water to the dispensing unit and electrical signals to the water valve and to the ice ejecting mechanism which delivers ice from the bin supplied by the ice maker to the exterior. Furthermore, it is necessary to provide a moveable door to open and close to allow the ice to be dispensed while sealing to prevent any outside air from entering the refrigerator. Thus, it has been difficult to assemble and to insulate the dispensing unit, and heretofore, the insulation around the dispenser has generally been formed from separate pieces which must be assembled after the dispensing unit has been mounted on the door and held in place when the interior liner of the door is attached. This not only results in increased cost of manufacture, but generally results in a poorer overall insulation performance causing greater heat loss than through a normal door without the dispensing unit.